Ken Morgan

Robert Lowery

Prof. Ernst

George Macready

First Cop with Thor

Charles King

Police Inspector Hamilton

Kenneth MacDonald

Mason

Bud Osborne

Thor

Ray Corrigan

Prof. Marsden

John Elliott

Zoo Guard

Kit Guard

Prof. Franklin Arnold

Ralph Morgan

Babs Arnold

Carole Mathews

Flash

Willie Best

Dick Nordik

Jack Ingram

Joe Flint

Anthony Warde

Joe Butler

Ted Mapes

Blake

Eddie Parker

Mead

Stanley Price

Stunts

Eddie Parker

Director

Howard Bretherton

Screenplay

Royal K. Cole

Screenplay

Sherman L. Lowe

Music

Lee Zahler

Editor

Dwight Caldwell

Editor

Earl Turner

Stunts

Ted Mapes

Director of Photography

L. William O'Connell